The purpose of the Epidemiology and Biostatistics Core (EBC) is to provide all projects in this SCOR with guidance and collaboration regarding study design and data analyses. The EBC will play a central role in integrating the basic science of the animal study, the human population study (epidemiology), and the biomedical/clinical and experimental/clinical investigations. The EBC has two overarching goals: 1) facilitating the goals of the projects and enhancing integration of inter-disciplinary research and translation of basic health science and epidemiologic and clinical investigation into practical tools for the diagnosis, prevention and treatment of musculoskeletal disease in clinical and community-based populations; and 2) providing guidance and collaboration for all four projects and pilot projects regarding study design, data management and data analyses. The EBC will provide advice and collaboration in hypothesis formulation, experimental and study design, selection of comparison groups, inclusion and exclusion criteria, random assignment of participants in the two clinical trials, standard data collection instruments and methods (including quality control measures for data collection), selection of and criteria for potential confounding variables, appropriate statistical analytic techniques and interpretation of results of data analyses. The investigators in the EBC will work with the project investigators to develop, implement, analyze and write up the results of the projects of this SCOR. The EBC has four primary aims: 1) to provide high quality consultation and collaboration in the design of the studies of this SCOR, working closely with project leaders and investigators to design research questions and data collection tools that will facilitate appropriate and accurate analyses of data and appropriate selection of study groups to provide efficient designs; 2) to provide assistance in developing and implementing data management systems to facilitate effective, efficient and secure management and analyses of data; 3) to provide appropriate and timely quantitative statistical analyses for all projects; and 4) to provide appropriate, insightful interpretation of the results of statistical analyses provided to the projects. The Co-Directors of the EBC have decades of experience and well- established expertise in study design, data collection, and statistical analyses for both observational and experimental (specifically, clinical trial) studies and are well-equipped to make decisions jointly for this Core. They also have extensive experience in collaborating with investigators from many different disciplines and are dedicated to inter-disciplinary collaboration and providing well-informed advice.